Below are a few free quality tests that we prefer:

Personality Hacker
Personality Hacker features a good test. Their services are thoughtful, they feature unique content that’s delivered in a way that appeals to an alternative market.

A note:

The ENTP community does not recommend testing at www.16personalities.com or relying on their type descriptions. Their testing methods tend to be inferior and they attempt to typecast every personality as a fixed binary. 16 Personalities exists as an easy alternative for a population obsessed with social media personality quizzes and astrology.